Carburetor



1,635,433 July 12, 1927. M F. PURVEY CARBURETO R 2 Sheets-Sheet '1 Filed July 1'7, 1922 IN VEN TOR. yore/012i. Par-way.

y/? in? w ATTORNEY.

- July 1927' M. F. PURVEY CARBURET OR Filed July 17, 1922 2 Sheets-Sheet 2 I IN VEN TOR. lforeiolr F. Purl/0y ATTORNEY.

Patented July 12, 1927.

'nui'r ST ATENT E vronn'ron F. PUBVEY, or DETROIT, MICHIGAN, ASSIGNOR TOITHE rUR-vEYio R BURETOR CORPORATION, A CORPORATION OF DELAWARE.

' 1,635,433 use CARBURETOB.

This invention relates to carburetors and the object of the invention isto provide a carburetor of simple construction and efficient operation in which the liquid fuel is fed into the air conduit ina fine mist or fog. The principal object of the invention is to provide a carburetor having two fuel inlets extending into the air conduit, the said inlets being each provided at the discharge ends with a chamber containing a ball about which the fuel must pass andwhichis rapidly vibrated by the fuel passing thereabout. A further object of the invention is toprovide a carburetor of the character described comprising a pair of fuel inlets each provided with a ball in the end thereof over which the fuel is spread in a thin film while beingdrawn from the fuel inlets, the. liquid fuel being discharged from the fuel inlets into the. air conduit in'a fine mist or fog.

A further object of the invention is to pro-V vide a carburetor of the character described comprising a throttle valve adapted when closed to prevent flow of fuel from one of the fuel inlets and also prevent flow of air through the air conduit at the same. time allowing flow of fuel from the other fuel conduit, the said valve when opened allowing flow of air through the air conduit and flow of fuel from both fuel inlets. These objects and the several novel features of the invention are hereinafter more fully described and claimed and the preferred form of construction by which these objects are attained is shown in the accompanying draw ings in which- Fig. 1 is a plan view of a carburetor embodying my invention. i u I Fig. 2 isa side elevation-thereof.

Fig. 3 is a section taken on line 3'3 of F ig; 1.

Fig. 4 is a section taken on line 4- .1; of Fig. 3.

Fig. 5 is a section taken on line 5-5 of Fig. 6 is a section through the air conduit of the carburetor. I

Fig. 7 is a detail of a section through one of the nozzles.

As shown in Figs. 1 and 5,-a bowl 1 is preferably provided and a connection 2 for a liquid fuel lineis threaded onto a boss- 3 on the bottom of the bowl. A needle valve 4 is provided for closing the fuel inlet 5 and a pivoted arm 6 is provided for operating the needle valve 4., thearm being 'secured to a float 7 within the bowl. The bowl is provided with a pairof enlargements 8 and 9 on one si-de'as, shown in Figs. 2 and 3'whic'h areprovided with vertical channels 10 in communication with the bowl by means of the channels 11 opening thereinto. Opening into each channel 10 is an air inlet channel 12 having an air tube 13 in communica- 7 tion' therewith and through which the air may Pass. The channelslO at the PP end are restricted and provided'with small aperturesld therethrough vandtamember 15 is threaded into the upper end of the enlargement 8 and a member 16 isthreaded into the upper end of. the enlargement 9. Both of these members 1 5 and 16Iare provided with apertures 17 in communication with the apertures 14 of the members 8 and 9 and at the upper'end each member 15 and 1% is provided with a chamber or recessQlSJ Within each chamber 18 is a ball 19 normally closing the aperture 17 and a pin2O I is provided through the upper end of each' member 15 and 16Which prevents the ball 19 from being drawn "out of the recess or;

chamber 18 by the suction of the engine.

The air conduit 21' is slipped over the memi berslo and 16 and is bolted to a lug 22 on Q the .bowl' by [means of. a bolt 23 passing through thelug2 1 asshown in Fig. 3. "This air conduit 21 is provided, as shown in Figs.

1 and 2, with an. air inlet 25 having a but I terflyvalve'26 therein which is operable by a'bell crank 27 to regulatethe fiow of air, the valve 26 being provided with a spring 28 normallyholding the valve in the open position. This air conduit 21 is provided with a baflie 36'between the air inlet end 25 and the throttle valve so that the air is directed through the oblong Opening 37 be fore passing about the fuel inlets. By passing the air through the, restricted opening 37 a vacuum is produced about th'e fuel in lets which aids in drawing the fuel into the intake manifold as will be'readily under stood. As shown more particularly in Fig. 3 the throttle valve 29 in the air conduit is provided with an aperture3l which registers over the chamber 1.8 of the member 16 when closed. By this means when the throttle valve is closed the air conduit is closed with the exception of the aperture 31 and the liquid fuel is not drawn through the member 15, the entire supply of liquid fuel and air flowing through the member16 and providing a rich mixture for starting the engine and for idling.

' Iii-operation the liquid fuel flows into the bowl 1 until the cork float 7 is in the position shown in full lines in Fig. 5. At this time the level of the gasoline is atabout the line AA shown in Fig. 3 and partially fills the horizontal apertures 12. When the engine is started the throttle valve 29 is closedas shown and the entire vacuumproduced by the engine is relieved through the aperture 31 ofthe said throttle valve. This vacuum draws air through the tube 13 and-through the; aperture 12 where the air is mixed with the gasoline and passes upwardly through the small aperture 14 through the aperture 17 of the member 16 and through the chamber 18 about the ball 19 andinto the air conduit, through the aperture 31 of the throttle valve. The liquid fuel in passing-upwardly through. the aperture 17 is spread overthe'ball .19 and on account of the vacuum the ball .19 is practically maintained betweenthe pin 20 and its seat and the mixture of fuel and air passes through the aperture 31 in. a fine mist or fog. This provides a richmixture for starting the engine and for idling speeds and when the throttle valve 29,is opened, as shown in dotted lines inIFigB and full lines in Fig. 1, the air flows through the air inlet and in: passing over the upper end of the members 15 and 16' air is drawn through the tubes 18, apertures 12, the small apertures 14, through the aperf tures 17 and about the balls 19 into the air conduit, the air being mixed with the liquid fuel in the channel 12 and by vibration of the balls 19 the mixed air and fuel passes into the air conduit as a mist or fog where it is fur ther mixed with air. hen the throttle valve 29 is open as shown in Fig. 6 the mixed air and fueljis drawn through both members 15 and 16 which causes both balls 19 to vibrate very rapidly so that the liquid fuel is broken up into fine particles and is drawn into the 51130011611111? m a fine vaporized state. As

shown in Fig. 2 a pair of adjusting screws of the throttle valve 29 allows a sufficient flow of gasoline for idling speeds and open ing of the throttle valve provides a leaner mixture for a higher range of speed. It will also be noted that this carburetor is very safe and practically fireproof in use. For instance, should the timing of the engine be disarrangedand a backfire occur in the air conduit 21, the pressure will cause the balls 19 to seat tightly and close the fuel feed apertures 17 thus preventing the fire from coming in contact with the liquid fuel which often results disastrously.

From the foregoing description it'becomes evident thatthe device is very simple and efiicient in operation, may be easily and cheaply manufactured, is formed of few parts which will not easily get out of order and provides a device which accomplishesthe objects described.

Having thus fully described .my invention, its utility and mode of operation, what I claim and desire to secure by Letters Patent of the United States is In a carburet r, a main airconduit, a. pair of fuel feed lines extending. into the conduit and terminating at different heights therein, the fuel conduit of greatest height having a recessed end portion terminating in a plane at a right angle to the axis of the conduit, a ball iii-the recess of less diameter'than the said recess and normally closing said conduit, a throttle valve'in the air conduit adapted when open to subject bot-h fuel feed lines to influence of air passing therethrough, said throttle valve being adapted to be turned. to closed position to lie in contact'with the end of the fuel conduit of greatest height,

said valve having an opening of less diameter than the said recess at .the conduit end and providing when the valve is closed a discharge opening for the said highest fuel feed conduit into the main air conduit above the valve, the throttle valve otherwise practically closing the conduit to flow of air therethrough, each fuel feed conduit being connected with a source of fuel supply and each having a second conduit connected therewith opening to atmosphere, and an air inlet conduit for the said main air conduitprovlded with a restricted opening thereinto.

In testimony whereof, I sign this speciiication.

MORETON r. PURVEYJ 

